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North Carolina Tar-Pamlico River Basin Plan. Final Scoping Meetings January 30 and 31, 2001. North Carolina Cooperating Technical State Flood Mapping Program Overview. Purposes of the NFIP. 1. Make flood insurance available 2. Identify floodplain areas and flood risk zones
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North Carolina Tar-Pamlico River Basin Plan Final Scoping Meetings January 30 and 31, 2001
North CarolinaCooperating Technical State Flood Mapping Program Overview
Purposes of the NFIP 1. Make flood insuranceavailable 2. Identify floodplainareas and flood risk zones 3. Provide framework for a community’s floodplain management ordinances
Importance of Updated Flood Hazard Information • With up-to-date flood hazard data: • Map users can make prudent siting, design, and flood insurance purchase decisions • Communities can administer sound floodplain management programs
North Carolina’s Flood Mapping Program • Program established to implement the Cooperating Technical State (CTS) Partnership with FEMA, signed September 15, 2000 • Ownership and responsibility for Flood Insurance Rate Maps (FIRMs) delegatedto State
Why North Carolina Is Undertaking This Project • State’s vulnerability to hurricanesand flooding • 14 federally declared disasters since 1989 • Hurricane Floyd damages = $3.5 billion • 4,117 uninsured/under-insured homes destroyed as result of Hurricane Floyd • Accurate, up-to-date flood hazard information crucial to protect livesand property
Why North Carolina Is Undertaking This Project • Hurricane Floyd revealed flood hazard data and map limitations • Age of North Carolina FIRMS • 55% at least 10 years old • 75% at least 5 years old • FEMA’s mapping budget is finite • North Carolina receives only one updatedflood study for one county per year • Many counties and communities lack resources to take on this responsibility
Benefits of North Carolina’s CTS Program • Current, accurate data for sound siting and design decisions • Better floodplain management to reduce long-term flood losses • Updated data to alert at-risk property owners of the need for flood insurance • Faster, less expensive FIRM updates
Program Components • Developing flood hazard studies through community mapping needs analysis (Scoping) • Acquiring high-resolution topographic data and accurate Digital Elevation Models (DEMs) • Conducting engineering studies • Generating countywide digital FIRMs (DFIRMs) • Designing and implementing state-of-the-art, dynamic IT infrastructure • Supporting real-time flood forecasting and inundation mapping capability
+ + Topography Flood Data Base Digital FIRM = Digital FIRMs
Digital FIRMs • Digital FIRMs will be produced in a countywide format • Will depict all flood hazard data • FIRM panels will be consistent with USGS DOQ tiling scheme
Community Review and Due Process • Preliminary FIRMs provided when Tar-Pamlico River Basin Study is complete • 90-day appeal period • Preliminary Countywide FIRMs provided when adjacent basin studies are complete • All appeals evaluated and resolved • Final Effective FIRMs provided and made available by the State on its Information Management System
Additional Benefits of the CTS Program • Digital format to allow: • More efficient, precise flood risk determinations • Geographic Information System (GIS) analysis and planning • Online access 24 hours a day • DEMs will be useful for almost any engineering or planning application
Tar-Pamlico River Basin • Extends from its headwaters in the north central Piedmont section of North Carolina to the Atlantic Ocean • Most of the upstream portion (Tar River) is freshwater, whereas the downstream portion (the Pamlico River) is entirely estuarine • Comprised of portions of 19 counties and 53 municipalities
Scoping Phase for Tar-Pamlico River Basin The Scoping Phase determines: • What areas are floodprone and need flood hazard data developed • Determine appropriate technical method for developing up-to-date flood hazard data and establish priority level • How flood hazard data will be presented on FIRMs
SCOPING PRODUCTION Step 1 Step 2 Step 3 Step 4 Step 5 Initial Research and Community Coordination Initial Scoping Meeting Draft Basin Plans Final Scoping Meeting Final Basin Plans State KickoffMeeting with County/Local Floodplain Administrators Questionnaire State Prepare Delivery Orders& CTC Mapping Activity Agreements & Update CTS Mapping Agreement Develop Draft Basin Plans MappingNeeds Assessment Generate Initial Scoping Package NCScoping Database InitialScoping Meetings Final Scoping Meetings Finalize BasinPlans Analysis and Mapping FEMA EffectiveFIS & FIRM Research FEMA Process for Scoping Six River Basinsin Eastern North Carolina EvaluatePost-FloydData
Step 4 — Final Scoping Meeting THIS IS WHERE WE ARE TODAY! • All impacted counties and communities invited • Two separate Final Scoping Meetings: • January 30th - Greenville, NC • January 31st - Tarboro, NC • Draft Tar-Pamlico River Basin plan presented • Provides final opportunity for input
Step 5 — Final Basin Plan • Draft Basin Plan may be revised following the Final Scoping Meetings • Watershed Concepts, the State’s Floodplain Mapping Contractor for the Tar-Pamlico River Basin, will develop proposals for the State • Tar-Pamlico River Basin Plan will be finalized and distributed to impacted counties and communities • Production phase will then begin
North Carolina Tar-Pamlico River Basin Meeting QUESTIONS ON THE SCOPING PHASE ? ? ?
Draft Tar-Pamlico River Basin Plan • Summarizes scoping phase • Outlines how base maps and topography will be acquired • Proposes engineering methods by which each flooding source reach will be studied • Describes the process and schedule for completing the map production
Detailed Study — Riverine • This method requires the following: • DEMs • Field surveys • Channel bathymetry • Bridge/culvert opening geometry • Channel and floodplain characteristics • Detailed Hydrologic and Hydraulic Analyses • 10%, 2%, 1%, and 0.2% annual chance flood elevations and boundaries identified (Zone AE) • Floodways delineated
Redelineation • This method requires the following: • DEMs • Effective FIS flood elevations Proposed for all areas currently shown on effective FIRM as Zone AE or VE and not being restudied
Approximate Study • This method requires the following: • DEMs • Delineation of 1% annual chance floodplain boundaries using approximate methods • Does not include collection/use of field-collected topographic data or bridge/culvert data Proposed for all areas currently shown on effective FIRM as Zone A and not being restudied in detail.
Use of Effective Information • This method involves no new analyses or floodplain mapping • Effective FIS and FIRM data are digitized and fitted to updated base map This method is not anticipated to be used for any communities in the Tar-Pamlico River Basin
Schedule for FIRM Production (cont’d)
Community Review and Due Process • Preliminary FIRMs provided when Tar-Pamlico River Basin Study is complete • 90-day appeal period • Preliminary Countywide FIRMs provided when adjacent basin studies are complete • All appeals evaluated and resolved • Final Effective FIRMs provided and made available by the State on its Information Management System
North Carolina Tar-Pamlico River Basin Meeting QUESTIONS ON THE DRAFT BASIN PLAN ? ? ?